US2322880A - Process of pickling, curing, and preserving fruits and vegetables - Google Patents

Description

- spices and condiments are added.

Patented June 29, 1943 "UNITED STATES-PATENT OFFICE raocsss or PICKLING, ermine, AND ran- SERVING FRUITS AND VEGETABLES 7 Alfred Pollak. New York, N. Y.

No Drawing. Application June 5, 1941,

Serial No. 396,708

\ 710mm. (cits-456) This invention relates to a method of improving preserves of vegetable matter, such as for example cucumbers. I

The word vegetable as used in this specification includes herbaceous plants, roots, bulbs,

as well as fruits and generally all matter belong ing to the vegetable kingdom.

Vegetables decay unless specially. treated or kept in cold storage, Such specially treated vegetables are usually called preserves." Besides this primary purpose, preserving methods is equally applicable to other preservin methods.

The chemical changes taking place during the rpmcessuo of preserving foodstufl's, briefly are, as 0 we:

Vegetables are preserved by keeping them-in pickled and cured in a very short time after the Atthe present time, the fola salt brine, which is concentrated enough to keep out all deleterious fermentations, but which is not too strong to prevent a spontaneous acid fermentation, such as a lactic acid fermentation. 'lhe formed lactic acid serves as a preservative, and the green goods can be stored for a. very V longtime without refrigeration and without the danger of being spoiled by some other unfavorable fermentation. At the same time an osmotic process takes place between the constituents of the goods and of the brine. Salt enters. into the body of the vegetables, while certain soluble Certain parts of the vegetable crop have to be harvest and must be brought to the consumer as quickly as possible. A good example for this isthe so called genuine dill pickle." Their fermentation has to be practically finished in but a few weeks. The salt brine must be much weaker than in theprevious cases. and condiments are added directly to the salt brine and must be used up in a much'shorter period. A quickened and healthysour fermentation. in the case of dill pickles, is therefore of paramount importance. Their taste and value as a wholesome condimentare of course much superior to those of goods made exclusively out of salted stock. The reason for this is that they need not undergo such extensive brining and consequent leaching processes. Naturally. the

soluble mineral constituents,-and the vitamins present in the fruit, are much better preserved. In the case of sauerkraut, sour cabbage, sour shredded beets, the technical situation is some-' what different, because there is no extra salt brine used. The shredded goods are stored in wooden containers, and in forming layer after layer during their manufacture, a certain amount of salt is added in between layers. Subsequently, by osmosis and autolysis, the moisture of the goodsis released and forms a juice which contains, besides the originally added salt, all the soluble parts of' the shreds brought in solution such as sugars, mineral salts as well as nitrogencontaining compounds. In this juice a spontaneous sour fermentation seon takes place to form a preserving medium which is similar to the case discussed above.

A special problem is encountered in the case of cucumbers and more particularlywith the socalled genuine dill pickles," The main difiiculty is that after a short time the formation v of a parasitic yeast scum starts in the dill pickle substances migrate from the body into the brine,

such as sugars, and certain raw and harsh tasting components of the body fluid. By a spontaneous sour fermentation, the sugar is converted mostly into lactic acid, the whole taste of the 'goodsis changed favorably, and the tissues of the bodies. are mellowed at the same time by ensymatic'actions. However. 80 0ds preserved in a strong salt brine have to be processed before being packed into the ultimate containers to rid them of the surplus salt which would make them unpalatable. Moreover, sugar, vinegar and other megatherium, mesentericus and others.

' containers in which torula yeast, wild yeast and.

mycoderma develop. The parasites ferment the sugar present, eat up the lactic acid, form carbonic acid gas and bring .the closed barrels to explosive condition. Besides this drawback, the

disappearance of the lactic acidallows the rapid growth of certain pectin-decomposing bacteria, such as Bacillus protons, Bacillus vulgatus, They soften the cured goods, make them slimy and finally spoil them.

As in most spontaneous ferm'entations; so in the commercial manufacture of pickled goods,

many hazards and uncontrollable influences are The spices encountered. It is, of course, of great importance to always produce uniform merchandise of the same quality and flavor.

It is the object of the present invention to overcome these and other dimculties as will become apparent from the followingdescription.

In brief, I discovered that preserving processes are greatly and unexpectedly improved by an addition of steepwater." Steepwater is a waste product obtained in the 'inanufacture of com contained in the materials mentioned,

As the steepwater from starch factories is at present the most typical and economical representative of these additional materials, the calculations in the following practical examples are based on its use.

The average constitution of steepwater," calculated on the basis of dry substances, is substantially as follows:

a Per cent Nitrogen-containing substances, including amino acids (calculated as Carbohydrates 11-15.

Total acids (calculated as lactic acid) of which about 50% are lactic acid 12-17 Mineral matter 15-18 which include:

P205 69 C'aO 0.3-0.0

I found that an admixture of steepwater for and tomatoes because there sugar is migratingtoo slowly from the inside of the fruit into the brine. Therefore, the formation of the lactic acid is too. slow and the danger of a faulty fermentation becomes too great.

The initial addition of lactic acid to the .brine to start the fermentation in a rather sour medium produces an improvement because the lactic acid allows a selective sour acid fermentation and keeps out putrid fermentatlons. However, this improvement does not produce nearly as good results as the process according tomy invention. a a

In this connection it should be noted that in some years and in certain regions, cucumbers with very thick skins are grown and the same are delivered to the pickle manufacturer for quick curing. The osmosis in such a case is going on too slowly and it is quite impossible to leach out the raw and bitter taste present in such fruits in the short time during which the goods are undergoing fermentation and curing. Similar difliculties are encountered in the pickling of other kinds of vegetables.

These and other diiiiculties are completely overcome by the present invention. The invention, both on an experimental and on a large scale, produced unexpected results. Not alone-'- did the sour fermentation start earlier and proceed longer and further but also the formation of yeast scum was stopped almost completely in batches treated according to the invention. In contrast thereto, in parallel'batches to which lactic acid was added in amounts to have the same acidity at the start of'the fermentation as in the batches according to the invention,

' yeast scum was formed as usual. No yeast scum and no spoilage occurred in the batches treated instance caused a vigorous lactic acid fermenta-.

I found that the presence of amino-acids was very favorable in furthering the development of lactic acid and buffering the acid effect so that a higher maximum of acid was formed in a very short time.

After many experiments, I discovered. that steepwater is a very favorable substratum for a quick start of the lactic ferment and it carries the acid formation to a higher maximum than .it was possible to reach heretofore. The results thus obtained are more favorable than 'in cases in which the brine was inoculated with charges of pure cultures of acid forming bacteria. Vegetables treated with such cultures during the pickling process acquire a flavor and aroma" 'tion from the very beginning whereby obnoxious fermentation was eliminated. At the same time quite different and lacking in body. Besides, it

is practically impossible to sterilize the green raw material thoroughly enough before inoculation with a pure culture. 1

Heretofore, sugar has been added directly to the first pickling solution inorder to improve the lactic acid fermentation. However,- this addition of sugar fails to produce results comparable with those, of the present invention. This is especially true in the case of cucumbers in accordance with the invention.

Furthermore, at the same time a much faster and stronger osmosis between the brine and the body of the fruit to be pickled was obtained in these batches. I discovered that this result was due to the higher lactic acid formation in a strongly buffered medium ands. stimulated action of the hemicellulose=dissolving enzymes in the fruit body. The result ofthis was a much faster curing of the pickles. Even bitter and harsh tasting fruits, which under normal processing could not be used at all for this purpose, became sweet and palatable in a short time.

with the disappearance of all yeast formation,

which isa source of constant loss to the manu-' facturer. a considerable improvement in. the quality of the finished pickles was obtained. The processed goods preserve a fresh and sweeter taste much longer and their texture stays crisp much longer. I also found that these products keep their green color for a considerable time, a fact/which proves to be of great advantage in the production of half-sour pickles.

Another reason for these favorable results is; the elimination of all 'faulty fermentatio'ns and the simultaneous suppression of the yeast scum formation. 'I'hese I attribute to the presence oi the greatly invigorated lactic acid fermenta No development of deleterious fer'men-z tion. tations. as for instance those caused by bacteria belonging to the groups of Bacillus vulaatus.

I liquefying enzymes.

nets of their metabolism are changing the taste Bacillus mesentericus or subtllis-megatherium. These bacteria add to the spoilage of plant tissues by the formation of excessive amounts of At the same time the prodof vegetable matter in a very unfavorable way.

Also, discoloration may take place due to tensified oxydative processes. 7

I discovered that in preserving vegetables, phytins and their cleavage products produce a stimulating effect on the multiplying and acid forming capacity of the lactic acid bacteria. The phytin are preferably added in the form of phytin containing materials. time, it is the presence of amino-acids which is of importance, because they are a valuable nutrition for the stimulated bacteria and simultanenor isolated. In some cases these components have only been summarized as "bois complex." These components act like phytohormones. In combination with the above defined active ingredients, these undefined components exercise a selective action on the various organisms involved in the preserving of vegetables. These undefined substances favor th development of the lactic acid forming bacteria, and are completely inhibiting the development of yeast organisms. Otherwise; it would not be possible, that in one case where lactic acid is added to the fermenting batch, the yeast formation is as usual or even increased, whereas, in a batch of exactly the same composition, but where one of the described extracts according to the invention is added, no formation-of yeast takes place at all, as above'described.

These results were unexpected and are highly important to the pickling industry.

My invention also produces a favorable action on finished products when they are added to the brine in the ultimate container. Certain products, such as so called old fashioned "pic'calilli and pickled beets which are very perishable, have to be sterilized before delivery to the trade and the containers when onc opened have to be kept under refrigeration to avoid rapid spoilage.

- This condition can be ameliorated when the acid content of thebrine is kept much higher. But this must be done without damaging the palatability by using a buifering substance which camoufiages the higher acidity.

Illustrative examples of carrying out the present invention are given in the following:

Exsuru: I

I Genuine dill pickles wooden barrels .are filled with cucumbers, the usual spices and dill weed. Then the pickles are covered with a brine containing -28 salometer degrees of salt and 1 oz. of steepwater for every gallon of brine.

(In the absence of steepwater the brine has to be made more concentrated, 28-33 salom. 'degrees, otherwise the fermentation is very unclean.

The acidity of this brine may be increased with dill-vinegar of lactic acid to about 02-03%,

calculated as lactic acid. Then the barrels are closed and after two days they areopened again and the brine replenished to the. top. The barrels containing the steepwater are now closed airtight and kept closedfluring the whole period of curing. Due to the fact that the growth of yeast is very much restricted. there is no danger At the same asaasso 'The salt concentration was 28 salometer degrees in both cases at the start. Thisconcentration proved to be too low for the regular fermentation without steepwater, the pickles became partly soft. With the same salt concentration an excellent product was achieved in the barrels with added steepwater.

In spite of the lower salt concentration, which vouchsafes better palatabillty of the pickles, no addition of a preservative such as sodium benzoate is necessary to prevent spoilage.

Exulru: II

Pickling of greentomatoes, t mers and the like The method of pickling these vegetables is practically the same as the one described in connection with the pickled cucumbers. 'Steepwater is added to the brine at the rate of -'1 ounce per gallon. The products cured in such a brine taste sweeter. on account of the stronger buffering action. Therefore, it is possible to keep these brines on a higher acidity which adds to the proof explosion of the barrels. (In the absence oil I6 tection of the goods against spoilage. Nevertheless, taste Exsurizs III Manufacture of sauerkraut there is no brine used. Only the, genuine juice is formed by salting the shredded cabbage, thereby inducing osmosis and formation of the sauer kraut juice in which the sour fermentation takes place.

The addition of the vegetable compound is done in this way that for instance steepwater of 50- dry substance is diluted'with water, until it is liquid enough that it can be sprinkled on the layers of salt, which are imbedded between layers of shredded cabbage.

The amount of salt is between 2-3% of the total weight of the cabbage; the amount of steepwater added is 515% of the weight of the salt. or in this case, about 0.125-0. of the weight of the cabbage.

The results here are similar'to those reached with cucumbers. The maximum of acidity is reached in about half of the time it takes without the addition of the compound according to the invention. The taste of the finished product is mellower and the texture is more crisp.

E'xlulru IV llanu/acture ot. pickles, sauerkraut and the like by using starters tions. The underlying idea is to start the sour fermentation ina part of the goods, for instance 5-l%, to add to this part the whole of the finished goods do not have a too sour thenew compound, or if this should not be possible on account of a too high" acid or salt content, then at least 25-50% of it, This arrangement, will start in the respective fruits, or shredded vegetables a ve fast and strong selective lactic acid'fermen ion. As soon as this fermentation is well under way, this starter" is distributed uniformly in the bulk of the goods to be fermented; in this way a more uniform and stronger sour fermentation is obtained,v

I claim:

1. Improved method of preserving vegetables which consists in pickling the vegetables with a pickling solution containing, diluted therein, a

I substance selected from the group of organic acid and Dhytin containing waste products consisting of steepwater from corn starch factories, pressa two ounces of said selected substance is added to each gallon of brine.

4. The method of pickling vegetables comprising dividing the vegetables to be treated into a of vegetables, starting a strong fermentation in the starter portion and thereafter mixing the large bulk portion and a small starter portion,v

adding to the starter portion a substantial part of the steepwater intended for the total quantity starter and bulk portions with each other.

5. The method of pickling vegetables which comprises placing the vegetables in a brine, leaving the vegetables in the brine until maturity and completion of the pickling and thereafter in corporating steepwater in the brine'in which the vegetables are kept after completion of thepicks,

lingprocess.

6. An improved brine for preserving vegetables comprising an admixture of a substance selected from the group of phytin and organic acid containing waste products consisting of steepwater from comstarch factories, presswater from potato starch factor-la and spent washes from distilleries.

7.- Method of producing sauerkraut, comprising shredding cabbage, salting the same, and adding to the shredded and salted cabbage a phytin containing substance selected from the group of waste products consisting of steepwaterfrom comstarch. factories, pressyvater from potato starch factories, and spent washes from distilleries, the phytin containing substance added amounting toy from 5 to 15% of the weight of the salt mixed with the shredded cabbage.

ALFRED FOLLAK.